The present invention relates to a door latch device in a motor vehicle and particularly to a door latch device in a motor vehicle, the door latch device being placed in a double-lock state for deactivating unlocking of a lock knob inside the vehicle and a childproof lock state for deactivating an operation of an inside handle inside the vehicle.
Besides a normal lock and unlock mechanism, a door latch device in a motor vehicle provides the structure that shifts a double lock state that prevents a lock knob inside the vehicle from being wrongfully unlocked or shifted to an unlocking state, and the childproof structure for preventing a door from opening even if an inside handle is operated by children in the vehicle intentionally or wrongfully for opening as disclosed in WO2006/099730A1, particularly in FIG. 5.
However, in the door latch device therein, double lock is carried out by a double lock motor, while childproof locking is carried out by a childproof lock motor. To carry out both double locking and childproof locking, it is necessary to provide two motors involving high cost for manufacturing.